Edemagenic activity of aqueous form of muramyl dipeptide (MDP) in rats.

Repeated systemic administration of MDP in saline has been found to produce dose-dependent edema of paws in rats. Two to three daily doses are sufficient to induce significant increase of the paw volume. The edema is spontaneously well reversible. Its formation may substantially be reduced by indomethacin or prednisone, suggesting thus an involvement of prostaglandins. Body-weight loss and impaired walking of animals were also observed. Severity of all the effects was found to be markedly dependent on the strain of rats used.